Flightless birds are those that through evolution and the course of time decided to give up flight and stick to solid ground. At first it seems odd, given that the concept of flight is intrinsically linked with birds. But those who managed to adapt to a life on terra firma have for the most part thrived, species like the penguin and the ostrich. Yet there are many others that remain endangered. In some cases, critically so.
Click through and find out which birds missed their flight and ended up grounded.